US4621171A - Electroacoustic transducer and a method for manufacturing thereof - Google Patents

Electroacoustic transducer and a method for manufacturing thereof Download PDF

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Publication number
US4621171A
US4621171A US06499555 US49955583A US4621171A US 4621171 A US4621171 A US 4621171A US 06499555 US06499555 US 06499555 US 49955583 A US49955583 A US 49955583A US 4621171 A US4621171 A US 4621171A
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US
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Prior art keywords
plate
stationary
base
electrode
annular
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
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US06499555
Inventor
Hiroto Wada
Minoru Nishizono
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Toshiba Corp
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Toshiba Corp
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R19/00Electrostatic transducers
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49005Acoustic transducer
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49117Conductor or circuit manufacturing
    • Y10T29/49124On flat or curved insulated base, e.g., printed circuit, etc.
    • Y10T29/49155Manufacturing circuit on or in base
    • Y10T29/49156Manufacturing circuit on or in base with selective destruction of conductive paths
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49789Obtaining plural product pieces from unitary workpiece
    • Y10T29/4979Breaking through weakened portion

Abstract

An electroacoustic transducer includes a base plate made of insulating material, a stationary electrode formed on one side of the base plate and made of electrically conductive material, an annular support formed on the same side of the base plate and surrounding the stationary electrode, the annular support being made of the same electrically conductive material as the stationary electrode, and an electrically conductive diaphragm applied on the annular support.

Description

BACKGROUND OF THE INVENTION

This invention relates to an electroacoustic transducer and a method for its manufacture.

Various types of minature electroacoustic transducers or microphones are known such as the electroacoustic microphone shown in FIGS. 1 and 2 of the drawings, which is provided with an electrically conductive cylindrical casing 10 having an opening 12 for receiving sound waves. Base 14 is disposed in casing 10 and includes a recess 16 on its upper side facing opening 12 and aperture 18 in its center. Stationary electrode 20 is secured in recess 16 of base 14, and includes a plastic film 22 on metal plate 24 which functions as a conventional electret film.

Electrically conductive diaphragm 26 is mounted in parallel with opening 12 and stationary electrode 20, with the periphery of diaphragm 26 clamped between insulation spacer 28 mounted on stationary electrode 20 and electrically conductive ring 30 secured to the inner wall of casing 10. Diaphragm 26 is made, for example, of a metal film or a plastic film coated with a metal film and having a thickness of several microns. Metal plate 24 of stationary electrode 20 has protruding pin 32 on its under side to penetrate through hole 18. Protruding pin 32 and casing 10 function as as signal output terminals which is coupled to the desired circuit (not shown).

The electroacoustic microphone shown in FIGS. 1 and 2 is a rather complicated structure and presents problems from the standpoint of its operational characteristics, cost, size, and manufacturing process.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improved electroacoustic transducer having a less complicated structure compared to the prior art.

Another object of the present invention is to provide an electroacoustic transducer with improved operational characteristics.

A further object of the present invention is to provide an electroacoustic transducer which is relatively inexpensive.

A still object of the present invention is to provide an electroacoustic transducer which is relatively easy to manufacture.

Another object of the present invention is to provide an electroacoustic transducer which can be miniaturized.

A further object of the present invention is to provide an improved method for manufacturing an electroacoustic transducer.

According to the present invention, the electroacoustic transducer comprises a base plate made of an insulating material, a stationary electrode plate formed on one side of the base plate and made of an electrically conductive material, an annular support formed on the same side of the base plate and surrounding the stationary electrode plate and made of an electrically conductive material as the stationary electrode plate, and an electrically conductive diaphragm secured on the annular support and which defines an air gap with the stationary electrode plate.

Further, the method for manufacturing the electroacoustic transducer in accordance with the invention comprises the steps of providing an insulating base plate with at least a layer of electrically conductive material applied on one side of the base plate, forming a stationary electrode plate and an annular support surrounding the stationary electrode plate on said one side of the base plate by selectively removing the electrically conductive layer within areas on the base plate to leave the stationary electrode plate and the annular support, thinning the stationary electrode plate more than the annular support and thereafter applying an electrically conductive diaphragm on the annular support.

Additional objects and advantages of the present invention will be apparent to persons skilled in the art from a study of the following description and the accompanying drawings, which are hereby incorporated in and constitute a part of this specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing one example of a prior art electroacoustic microphone;

FIG. 2 is an exploded view showing the electroacoustic microphone of FIG. 1;

FIG. 3 is a cross-sectional view showing a preferred embodiment of the electroacoustic transducer according to the present invention;

FIG. 4 is a cross-sectional view of the electroacoustic transducer shown in FIG. 3 taken along Section lines A--A;

FIG. 5 is a cross-sectional view showing another embodiment according to the present invention;

FIGS. 6(a)-(d) are cross-sectional views showing the steps of manufacturing the electroacoustic transducer shown in FIG. 3;

FIG. 7 is a cross-sectional view showing a plurality of electroacoustic transducers manufactured in accordance with one example of the present invention; and

FIG. 8 is a plan view showing the plurality of the electroacoustic transducers of FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will be now described in detail with reference to FIGS. 3 to 8. Throughout the drawings, like reference numerals or letters are used to designate like or equivalent elements.

Referring first to FIGS. 3 and 4, a description will be provided of an electroacoustic transducer embodying the present invention. In FIGS. 3 and 4, base plate 40 is made of an insulating material such as fiberglass. Stationary electrode 42 made of an electrically conductive material such as copper is secured on one side of base plate 40. Base plate 40 has a thickness of about 1 millimeter, and stationary electrode 42 has a thickness of less than 1 milimeter and a diameter of about 4.5 to 8.5 millimeters.

Electret film 44 is secured on the top of stationary electrode 42, and has the same diameter as stationary electrode 42 and a thickness of several microns to several tens of microns. Annular support 46 is made of the same electrically conductive material as stationary electrode 42 and is secured on the same side of base plate 40 and surrounding stationary electrode 42. The annular support 46 has an outer diameter of about 6 to 10 millimeters, an inner diameter of about 5 to 9 millimeters, a thickness of about 1 millimeter, and is about several microns to several tens of microns thicker than the total thickness of stationary electrode 42 and electret film 44.

First terminal 48 is made of an electrically conductive material such as copper and is secured on the other side of base plate 40. Stationary electrode 42 and first terminal 48 are electrically connected to each other by first conductor 50 made of electrically conductive paste filled in through-hole 52, passing through stationary electrode 42, base plate 40 and first terminal 48. Second terminal 54 made of the same conductive material as first terminal 48 is also secured on the other side of base plate 40 and confronting annular support 46. Second terminal 54 and annular support 46 are electrically connected to each other by second conductor 56 made of the same electrically conductive paste as first conductor 50, which is filled in through second throughhole 58, passing through base plate 40 and second terminal 54 adjacent of the outer periphery of annular support 46. First and second terminals 48 and 54 have the same thickness of about several tens to several hundreds of microns.

Electrically conductive diaphragm 60 having plastic film base 60a and metal layer 60b coated on plastic film base 60a is secured on annular support 46 at the top end. Diaphragm 60 is arranged in parallel with electret film 44 on stationary electrode 42 and forms an air gap having a thickness of about several or several tens of microns with electret film 44. Cylindrical casing 62 made of an electrically conductive material such as copper or aluminum is mounted on base plate 40 and covers annular support 46 and diaphragm 60. Casing 62 has legs 64, which respectively extend downwards from the bottom end of casing 62, passing through base plate 40 and connected to second terminal 54 on the other side of base plate 40. Casing 62 has an opening 66 at its top facing diaphragm 60. Cylindrical wall 68 of casing 62 has a diameter of about 8 to 12 milimeters and a thickness of about several hundreds microns.

FIG. 5 illustrates another embodiment of the electroacoustic transducer according to the present invention. The modified embodiment shown in FIG. 5 is identical to the first embodiment shown in FIGS. 3 and 4 except that the impedance transforming device 70 is substituted for first conductor 50, and metal plate 72 is substituted for second conductor 56. Impedance transforming device 70 connects annular support 46 and second terminal 54, passing along the peripheral of base plate 40. Casing 62 is omitted in this embodiment.

FIG. 6 illustrates the steps for manufacturing the electroacoustic transducer shown in FIGS. 3 and 4. As shown in FIG. 6(a), raw material 80 is used as insulating base plate 40, and first and second metal foils or leafs, such as copper foils 82 and 84 are respectively applied to different sides of base plate 40. First metal foil 82 on one side of base plate 40 has the same thickness as annular support 46 shown in FIG. 3. Second metal foil 84 on the other side of base plate 40 has the same thickness as first and second terminals 48 and 54 shown in FIG. 3.

First metal foil 82 is processed in a first etching operation according to conventional techniques to leave only a round disc portion or stationary electrode 42 and an annular portion or annular support 46, as shown in FIG. 3. Second metal foil 84 is also processed in a second similar etching operation to leave only a round disc portion or first terminal 48 and an annular portion or second terminal 54, also shown in FIG. 3. The first and second etching operations can proceed simultaneously or at different times. The areas of the first and second metal foils 82 and 84, except the portions forming stationary electrode 42, annular support 46 and first and second terminals 48 and 54 are then entirely removed.

As shown in FIG. 6(b), stationary electrode 42 formed on one side of base plate 40 is again processed in a third etching operation (similar to the first and second etching operations) to decrease its thickness so that it is thinner than annular support 46 by a prescribed dimension of several or several tens of microns. The prescribed dimension can be accurately controlled by regulating the etching operation time or the like.

As shown in FIG. 6(c), electret film 44 is applied on stationary electrode 42 after the third etching operation. Electret film 44 is prepared by charging a stable electric charge on a plastic film before or after its application on stationary electrode 42. Although charging of the stable electric charge on the plastic film can be done by various conventional methods, electret film 44 in this embodiment is preferably made in accordance to the method described in U.S. Pat. No. 4,356,049.

As shown in FIG. 6(d), first and second through-holes 52 and 58 are defined in base plate 40. First through-hole 52 penetrates electret film 44, stationary electrode 42, base plate 40 and first terminal 48. Second through-hole 58 penetrates annular support 46, base plate 40, and second terminal 54. Then, first and second through-holes 52 and 58 are filled with electrically conductive paste. The paste which forms first conductor 50 (FIG. 3) connects stationary electrode 42 to first terminal 48, and the paste which forms second conductor 56 (FIG. 3) connects annular support 46 to second terminal 54. After the paste fills in first and second through-holes 52 and 58, electrically conductive diaphragm 60 shown in FIG. 3 is applied on annular support 46 at the periphery of diaphragm 60. Diaphragm 60 is arranged in parallel with the electret film 44 formed on stationary electrode 42 and is separated therefrom to maintain the prescribed air gap with electret film 44.

Referring now to FIGS. 7 and 8, a modified method from the method illustrated in FIG. 6 for mass production of electroacoustic transducers is described. FIGS. 7 and 8 illustrate only a final step for manufacturing the acoustic transducers according to the present invention. The steps prior to FIGS. 7 and 8 are equivalent to the steps shown in FIG. 6. According to the modified method, a plurality of electroacoustic transducers 90 are formed on a single rectangular wafer 92 made of an insulating material such as fiberglass. Wafer 92 has a plurality of electroacoustic transducer regions or base plates 40 as shown in FIG. 3, aligned lengthwise and crosswise with each other. On every base plate 40, a stationary electrode 42, annular support 46, first and second terminals 48 and 54, etc. are formed in accordance with the steps of FIGS. 6(a) to 6(c). Then a single rectangular diaphragm sheet 94 having a plastic film base 94a and metal layer 94b coated thereon is applied across all of the plurality of electroacoustic transdcuers 90 and is then fixed to the annular ends of the respective annular supports 46. Sheet 94 is then trimmed to leave portions which form diaphragms 60 facing annular supports 46 and stationary electrodes. The electroacoustic transducers 90 are separated from one another by connecting regions 96 of rectangular wafer 92. Connecting regions 96 can comprise perforations 98 (FIG. 8) or V-shape grooves 100 (FIG. 7) which can be easily broken. Perforations 98 and V-shape grooves 100 are able to made at any time before or after applying diaphragm sheet 94. After manufacture of the plurality of electroacoustic transducer 90 described above, the individual transducers 90 can be separated by breaking connecting regions 96.

While the present invention has been described with reference to particular embodiments thereof, it will be understood by those skilled in the art that numerous modifications can be made without actually departing from the scope of the invention. Accordingly, all modifications and equivalents may be resorted to which fall within the scope of the invention as claimed.

Claims (7)

What is claimed is:
1. An electroacoustic transducer comprising:
a base plate of insulating material;
a stationary electrode secured to on one side of said base plate, said stationary electrode being made of electrically conductive material;
an annular support secured to on the same side of said base plate as said stationary electrode and surrounding said stationary electrode, said annular support being made of the same electrically conductive material as said stationary electrode and extending higher than said stationary electrode from said base plate;
an electrically conductive diaphragm secured on said annular support and facing said stationary electrode; and
an electrically conductive casing mounted on said base plate to house said stationary electrode, said annular support and said diaphragm together, said casing defining an opening facing said diaphragm.
2. An electroacoustic transducer according to claim 1, further coprising:
a first terminal formed on the other side of said base plate, said first terminal being made of electrically conductive material;
a first circuit means electrically connecting said stationary electrode to said first terminal and penetrating said base plate;
a second terminal formed on said the other side of said base plate, said second terminal being made of the same electrically conductive material as said first terminal and said casing being electrically connected to said second terminal; and
a second circuit means electrically connecting said annular support to said second terminal.
3. An electroacoustic transducer according to claim 2, wherein said second terminal is annular and surrounds said first terminal.
4. An electroacoustic transducer according to claim 3, wherein said first and second terminals are made of the same electrically conductive material as said stationary electrode and said annular support.
5. An electroacoustic transducer according to claim 4, wherein said first and second circuit means are respectively conductors.
6. An electroacoustic transducer according to claim 4, further comprising:
an electret applied on said stationary electrode.
7. An electroacoustic transducer according to claim 6, wherein said first circuit means is an impedance transforming device and said second circuit means is a conductor.
US06499555 1982-05-29 1983-05-31 Electroacoustic transducer and a method for manufacturing thereof Expired - Fee Related US4621171A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
JP57-92018 1982-05-29
JP9202382A JPS58209300A (en) 1982-05-29 1982-05-29 Transducer
JP57-92017 1982-05-29
JP9201882A JPS58209294A (en) 1982-05-29 1982-05-29 Transducer
JP9201782A JPS58209295A (en) 1982-05-29 1982-05-29 Transducer
JP57-92023 1982-05-29

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Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4704556A (en) * 1983-12-05 1987-11-03 Leslie Kay Transducers
US4764690A (en) * 1986-06-18 1988-08-16 Lectret S.A. Electret transducing
US4790021A (en) * 1986-07-24 1988-12-06 Akg Akustische U. Kino-Gerate Gesellschaft M.B.H. Electrostatic transducer
US4908805A (en) * 1987-10-30 1990-03-13 Microtel B.V. Electroacoustic transducer of the so-called "electret" type, and a method of making such a transducer
US4993072A (en) * 1989-02-24 1991-02-12 Lectret S.A. Shielded electret transducer and method of making the same
US5335286A (en) * 1992-02-18 1994-08-02 Knowles Electronics, Inc. Electret assembly
WO1998010252A2 (en) * 1996-09-06 1998-03-12 Northrop Grumman Corporation Wafer fabricated electroacoustic transducer
US6108433A (en) * 1998-01-13 2000-08-22 American Technology Corporation Method and apparatus for a magnetically induced speaker diaphragm
US20030068059A1 (en) * 2001-10-09 2003-04-10 Blok Marcel De Microphone having a flexible printed circuit board for mounting components
US6707920B2 (en) * 2000-12-12 2004-03-16 Otologics Llc Implantable hearing aid microphone
US20040109579A1 (en) * 2002-12-03 2004-06-10 Toshiro Izuchi Microphone
US20050101832A1 (en) * 2003-11-07 2005-05-12 Miller Scott A.Iii Microphone optimized for implant use
US20050101831A1 (en) * 2003-11-07 2005-05-12 Miller Scott A.Iii Active vibration attenuation for implantable microphone
US20050222487A1 (en) * 2004-04-01 2005-10-06 Miller Scott A Iii Low acceleration sensitivity microphone
US7065224B2 (en) 2001-09-28 2006-06-20 Sonionmicrotronic Nederland B.V. Microphone for a hearing aid or listening device with improved internal damping and foreign material protection
US20060155346A1 (en) * 2005-01-11 2006-07-13 Miller Scott A Iii Active vibration attenuation for implantable microphone
US20070009132A1 (en) * 2005-07-08 2007-01-11 Miller Scott A Iii Implantable microphone with shaped chamber
US20070167671A1 (en) * 2005-11-30 2007-07-19 Miller Scott A Iii Dual feedback control system for implantable hearing instrument
US20080132750A1 (en) * 2005-01-11 2008-06-05 Scott Allan Miller Adaptive cancellation system for implantable hearing instruments
US7415121B2 (en) 2004-10-29 2008-08-19 Sonion Nederland B.V. Microphone with internal damping
US20090112051A1 (en) * 2007-10-30 2009-04-30 Miller Iii Scott Allan Observer-based cancellation system for implantable hearing instruments
US7840020B1 (en) 2004-04-01 2010-11-23 Otologics, Llc Low acceleration sensitivity microphone
US8771166B2 (en) 2009-05-29 2014-07-08 Cochlear Limited Implantable auditory stimulation system and method with offset implanted microphones
USD753061S1 (en) * 2014-06-03 2016-04-05 Csir Transducer

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US5421213A (en) * 1990-10-12 1995-06-06 Okada; Kazuhiro Multi-dimensional force detector
US6314823B1 (en) 1991-09-20 2001-11-13 Kazuhiro Okada Force detector and acceleration detector and method of manufacturing the same
FR2697675B1 (en) * 1992-11-05 1995-01-06 Suisse Electronique Microtech A method for manufacturing integrated capacitive transducers.
US6282956B1 (en) 1994-12-29 2001-09-04 Kazuhiro Okada Multi-axial angular velocity sensor
US5953436A (en) * 1997-07-18 1999-09-14 Caterpillar Inc. Apparatus for generating an audible tone
US5894264A (en) * 1997-07-18 1999-04-13 Caterpillar Inc. Apparatus for generating an audible tone
JP4145505B2 (en) * 2001-05-10 2008-09-03 松下電器産業株式会社 Electret condenser microphone and a method of manufacturing the same
KR200330089Y1 (en) 2003-07-29 2003-10-11 주식회사 비에스이 Integrated base and electret condenser microphone using the same

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US3436492A (en) * 1966-01-17 1969-04-01 Northern Electric Co Field effect electroacoustic transducer
DE1939130A1 (en) * 1969-08-01 1971-03-25 Sennheiser Electronic Universal application capacitive microphone capsule
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US4447678A (en) * 1980-07-28 1984-05-08 Akg Akustische U.Kino-Gerate Gesellschaft Mbh Electracoustic transducer

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Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4704556A (en) * 1983-12-05 1987-11-03 Leslie Kay Transducers
US4764690A (en) * 1986-06-18 1988-08-16 Lectret S.A. Electret transducing
US4790021A (en) * 1986-07-24 1988-12-06 Akg Akustische U. Kino-Gerate Gesellschaft M.B.H. Electrostatic transducer
US4908805A (en) * 1987-10-30 1990-03-13 Microtel B.V. Electroacoustic transducer of the so-called "electret" type, and a method of making such a transducer
US4993072A (en) * 1989-02-24 1991-02-12 Lectret S.A. Shielded electret transducer and method of making the same
US5335286A (en) * 1992-02-18 1994-08-02 Knowles Electronics, Inc. Electret assembly
WO1998010252A2 (en) * 1996-09-06 1998-03-12 Northrop Grumman Corporation Wafer fabricated electroacoustic transducer
WO1998010252A3 (en) * 1996-09-06 1998-07-02 Northrop Grumman Corp Wafer fabricated electroacoustic transducer
US6108433A (en) * 1998-01-13 2000-08-22 American Technology Corporation Method and apparatus for a magnetically induced speaker diaphragm
US6707920B2 (en) * 2000-12-12 2004-03-16 Otologics Llc Implantable hearing aid microphone
US7065224B2 (en) 2001-09-28 2006-06-20 Sonionmicrotronic Nederland B.V. Microphone for a hearing aid or listening device with improved internal damping and foreign material protection
US20030068059A1 (en) * 2001-10-09 2003-04-10 Blok Marcel De Microphone having a flexible printed circuit board for mounting components
US7239714B2 (en) * 2001-10-09 2007-07-03 Sonion Nederland B.V. Microphone having a flexible printed circuit board for mounting components
US20040109579A1 (en) * 2002-12-03 2004-06-10 Toshiro Izuchi Microphone
US7171012B2 (en) * 2002-12-03 2007-01-30 Hosiden Corporation Microphone
US20050101831A1 (en) * 2003-11-07 2005-05-12 Miller Scott A.Iii Active vibration attenuation for implantable microphone
US7556597B2 (en) 2003-11-07 2009-07-07 Otologics, Llc Active vibration attenuation for implantable microphone
US20050101832A1 (en) * 2003-11-07 2005-05-12 Miller Scott A.Iii Microphone optimized for implant use
US7204799B2 (en) 2003-11-07 2007-04-17 Otologics, Llc Microphone optimized for implant use
US7840020B1 (en) 2004-04-01 2010-11-23 Otologics, Llc Low acceleration sensitivity microphone
US20050222487A1 (en) * 2004-04-01 2005-10-06 Miller Scott A Iii Low acceleration sensitivity microphone
US7214179B2 (en) 2004-04-01 2007-05-08 Otologics, Llc Low acceleration sensitivity microphone
US7415121B2 (en) 2004-10-29 2008-08-19 Sonion Nederland B.V. Microphone with internal damping
US20080132750A1 (en) * 2005-01-11 2008-06-05 Scott Allan Miller Adaptive cancellation system for implantable hearing instruments
US20060155346A1 (en) * 2005-01-11 2006-07-13 Miller Scott A Iii Active vibration attenuation for implantable microphone
US8840540B2 (en) 2005-01-11 2014-09-23 Cochlear Limited Adaptive cancellation system for implantable hearing instruments
US7775964B2 (en) 2005-01-11 2010-08-17 Otologics Llc Active vibration attenuation for implantable microphone
US8096937B2 (en) 2005-01-11 2012-01-17 Otologics, Llc Adaptive cancellation system for implantable hearing instruments
US8509469B2 (en) 2005-07-08 2013-08-13 Cochlear Limited Implantable microphone with shaped chamber
US7903836B2 (en) 2005-07-08 2011-03-08 Otologics, Llc Implantable microphone with shaped chamber
US20090141922A1 (en) * 2005-07-08 2009-06-04 Miller Iii Scott Allan Implantable microphone with shaped chamber
US20070009132A1 (en) * 2005-07-08 2007-01-11 Miller Scott A Iii Implantable microphone with shaped chamber
US7489793B2 (en) 2005-07-08 2009-02-10 Otologics, Llc Implantable microphone with shaped chamber
US7522738B2 (en) 2005-11-30 2009-04-21 Otologics, Llc Dual feedback control system for implantable hearing instrument
US20070167671A1 (en) * 2005-11-30 2007-07-19 Miller Scott A Iii Dual feedback control system for implantable hearing instrument
US8472654B2 (en) 2007-10-30 2013-06-25 Cochlear Limited Observer-based cancellation system for implantable hearing instruments
US20090112051A1 (en) * 2007-10-30 2009-04-30 Miller Iii Scott Allan Observer-based cancellation system for implantable hearing instruments
US8771166B2 (en) 2009-05-29 2014-07-08 Cochlear Limited Implantable auditory stimulation system and method with offset implanted microphones
US9635472B2 (en) 2009-05-29 2017-04-25 Cochlear Limited Implantable auditory stimulation system and method with offset implanted microphones
USD753061S1 (en) * 2014-06-03 2016-04-05 Csir Transducer

Also Published As

Publication number Publication date Type
DE3319311A1 (en) 1983-12-08 application
US4615105A (en) 1986-10-07 grant
KR860000640B1 (en) 1986-05-24 grant
DE3319311C2 (en) 1987-02-05 grant
GB8314336D0 (en) 1983-06-29 grant
KR840005006A (en) 1984-10-31 application
GB2122842A (en) 1984-01-18 application
GB2122842B (en) 1985-08-29 grant

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